/**
 * Copyright (c) 2006-2015, JGraph Ltd
 * Copyright (c) 2006-2015, Gaudenz Alder
 */
/**
 * Class: mxGraphHandler
 *
 * Graph event handler that handles selection. Individual cells are handled
 * separately using <mxVertexHandler> or one of the edge handlers. These
 * handlers are created using <mxGraph.createHandler> in
 * <mxGraphSelectionModel.cellAdded>.
 *
 * To avoid the container to scroll a moved cell into view, set
 * <scrollAfterMove> to false.
 *
 * Constructor: mxGraphHandler
 *
 * Constructs an event handler that creates handles for the
 * selection cells.
 *
 * Parameters:
 *
 * graph - Reference to the enclosing <mxGraph>.
 */
function mxGraphHandler(graph) {
  this.graph = graph;
  this.graph.addMouseListener(this);

  // Repaints the handler after autoscroll
  this.panHandler = mxUtils.bind(this, function () {
    this.updatePreview();
    this.updateHint();
  });

  this.graph.addListener(mxEvent.PAN, this.panHandler);

  // Handles escape keystrokes
  this.escapeHandler = mxUtils.bind(this, function (sender, evt) {
    this.reset();
  });

  this.graph.addListener(mxEvent.ESCAPE, this.escapeHandler);

  // Updates the preview box for remote changes
  this.refreshHandler = mxUtils.bind(this, function (sender, evt) {
    if (this.first != null) {
      try {
        this.bounds = this.graph.getView().getBounds(this.cells);
        this.pBounds = this.getPreviewBounds(this.cells);
        this.updatePreview(true);

        // Resets handlers after they have been refreshed
        window.setTimeout(
          mxUtils.bind(this, function () {
            if (this.livePreviewUsed) {
              this.setHandlesVisibleForCells(this.cells, false);
              this.updatePreview();
            }
          }),
          0
        );
      } catch (e) {
        // Resets the handler if cells have vanished
        this.reset();
      }
    }
  });

  this.graph.getModel().addListener(mxEvent.CHANGE, this.refreshHandler);
}

/**
 * Variable: graph
 *
 * Reference to the enclosing <mxGraph>.
 */
mxGraphHandler.prototype.graph = null;

/**
 * Variable: maxCells
 *
 * Defines the maximum number of cells to paint subhandles
 * for. Default is 50 for Firefox and 20 for IE. Set this
 * to 0 if you want an unlimited number of handles to be
 * displayed. This is only recommended if the number of
 * cells in the graph is limited to a small number, eg.
 * 500.
 */
mxGraphHandler.prototype.maxCells = mxClient.IS_IE ? 20 : 50;

/**
 * Variable: enabled
 *
 * Specifies if events are handled. Default is true.
 */
mxGraphHandler.prototype.enabled = true;

/**
 * Variable: highlightEnabled
 *
 * Specifies if drop targets under the mouse should be enabled. Default is
 * true.
 */
mxGraphHandler.prototype.highlightEnabled = true;

/**
 * Variable: cloneEnabled
 *
 * Specifies if cloning by control-drag is enabled. Default is true.
 */
mxGraphHandler.prototype.cloneEnabled = true;

/**
 * Variable: moveEnabled
 *
 * Specifies if moving is enabled. Default is true.
 */
mxGraphHandler.prototype.moveEnabled = true;

/**
 * Variable: guidesEnabled
 *
 * Specifies if other cells should be used for snapping the right, center or
 * left side of the current selection. Default is false.
 */
mxGraphHandler.prototype.guidesEnabled = false;

/**
 * Variable: guide
 *
 * Holds the <mxGuide> instance that is used for alignment.
 */
mxGraphHandler.prototype.guide = null;

/**
 * Variable: currentDx
 *
 * Stores the x-coordinate of the current mouse move.
 */
mxGraphHandler.prototype.currentDx = null;

/**
 * Variable: currentDy
 *
 * Stores the y-coordinate of the current mouse move.
 */
mxGraphHandler.prototype.currentDy = null;

/**
 * Variable: updateCursor
 *
 * Specifies if a move cursor should be shown if the mouse is over a movable
 * cell. Default is true.
 */
mxGraphHandler.prototype.updateCursor = true;

/**
 * Variable: selectEnabled
 *
 * Specifies if selecting is enabled. Default is true.
 */
mxGraphHandler.prototype.selectEnabled = true;

/**
 * Variable: removeCellsFromParent
 *
 * Specifies if cells may be moved out of their parents. Default is true.
 */
mxGraphHandler.prototype.removeCellsFromParent = true;

/**
 * Variable: removeEmptyParents
 *
 * If empty parents should be removed from the model after all child cells
 * have been moved out. Default is true.
 */
mxGraphHandler.prototype.removeEmptyParents = false;

/**
 * Variable: connectOnDrop
 *
 * Specifies if drop events are interpreted as new connections if no other
 * drop action is defined. Default is false.
 */
mxGraphHandler.prototype.connectOnDrop = false;

/**
 * Variable: scrollOnMove
 *
 * Specifies if the view should be scrolled so that a moved cell is
 * visible. Default is true.
 */
mxGraphHandler.prototype.scrollOnMove = true;

/**
 * Variable: minimumSize
 *
 * Specifies the minimum number of pixels for the width and height of a
 * selection border. Default is 6.
 */
mxGraphHandler.prototype.minimumSize = 6;

/**
 * Variable: previewColor
 *
 * Specifies the color of the preview shape. Default is black.
 */
mxGraphHandler.prototype.previewColor = "black";

/**
 * Variable: htmlPreview
 *
 * Specifies if the graph container should be used for preview. If this is used
 * then drop target detection relies entirely on <mxGraph.getCellAt> because
 * the HTML preview does not "let events through". Default is false.
 */
mxGraphHandler.prototype.htmlPreview = false;

/**
 * Variable: shape
 *
 * Reference to the <mxShape> that represents the preview.
 */
mxGraphHandler.prototype.shape = null;

/**
 * Variable: scaleGrid
 *
 * Specifies if the grid should be scaled. Default is false.
 */
mxGraphHandler.prototype.scaleGrid = false;

/**
 * Variable: rotationEnabled
 *
 * Specifies if the bounding box should allow for rotation. Default is true.
 */
mxGraphHandler.prototype.rotationEnabled = true;

/**
 * Variable: maxLivePreview
 *
 * Maximum number of cells for which live preview should be used. Default is 0
 * which means no live preview.
 */
mxGraphHandler.prototype.maxLivePreview = 0;

/**
 * Function: isEnabled
 *
 * Returns <enabled>.
 */
mxGraphHandler.prototype.isEnabled = function () {
  return this.enabled;
};

/**
 * Function: setEnabled
 *
 * Sets <enabled>.
 */
mxGraphHandler.prototype.setEnabled = function (value) {
  this.enabled = value;
};

/**
 * Function: isCloneEnabled
 *
 * Returns <cloneEnabled>.
 */
mxGraphHandler.prototype.isCloneEnabled = function () {
  return this.cloneEnabled;
};

/**
 * Function: setCloneEnabled
 *
 * Sets <cloneEnabled>.
 *
 * Parameters:
 *
 * value - Boolean that specifies the new clone enabled state.
 */
mxGraphHandler.prototype.setCloneEnabled = function (value) {
  this.cloneEnabled = value;
};

/**
 * Function: isMoveEnabled
 *
 * Returns <moveEnabled>.
 */
mxGraphHandler.prototype.isMoveEnabled = function () {
  return this.moveEnabled;
};

/**
 * Function: setMoveEnabled
 *
 * Sets <moveEnabled>.
 */
mxGraphHandler.prototype.setMoveEnabled = function (value) {
  this.moveEnabled = value;
};

/**
 * Function: isSelectEnabled
 *
 * Returns <selectEnabled>.
 */
mxGraphHandler.prototype.isSelectEnabled = function () {
  return this.selectEnabled;
};

/**
 * Function: setSelectEnabled
 *
 * Sets <selectEnabled>.
 */
mxGraphHandler.prototype.setSelectEnabled = function (value) {
  this.selectEnabled = value;
};

/**
 * Function: isRemoveCellsFromParent
 *
 * Returns <removeCellsFromParent>.
 */
mxGraphHandler.prototype.isRemoveCellsFromParent = function () {
  return this.removeCellsFromParent;
};

/**
 * Function: setRemoveCellsFromParent
 *
 * Sets <removeCellsFromParent>.
 */
mxGraphHandler.prototype.setRemoveCellsFromParent = function (value) {
  this.removeCellsFromParent = value;
};

/**
 * Function: getInitialCellForEvent
 *
 * Hook to return initial cell for the given event.
 */
mxGraphHandler.prototype.getInitialCellForEvent = function (me) {
  return me.getCell();
};

/**
 * Function: isDelayedSelection
 *
 * Hook to return true for delayed selections.
 */
mxGraphHandler.prototype.isDelayedSelection = function (cell, me) {
  return this.graph.isCellSelected(cell);
};

/**
 * Function: consumeMouseEvent
 *
 * Consumes the given mouse event. NOTE: This may be used to enable click
 * events for links in labels on iOS as follows as consuming the initial
 * touchStart disables firing the subsequent click event on the link.
 *
 * <code>
 * mxGraphHandler.prototype.consumeMouseEvent = function(evtName, me)
 * {
 *   var source = mxEvent.getSource(me.getEvent());
 *
 *   if (!mxEvent.isTouchEvent(me.getEvent()) || source.nodeName != 'A')
 *   {
 *     me.consume();
 *   }
 * }
 * </code>
 */
mxGraphHandler.prototype.consumeMouseEvent = function (evtName, me) {
  me.consume();
};

/**
 * Function: mouseDown
 *
 * Handles the event by selecing the given cell and creating a handle for
 * it. By consuming the event all subsequent events of the gesture are
 * redirected to this handler.
 */
mxGraphHandler.prototype.mouseDown = function (sender, me) {
  if (
    !me.isConsumed() &&
    this.isEnabled() &&
    this.graph.isEnabled() &&
    me.getState() != null &&
    !mxEvent.isMultiTouchEvent(me.getEvent())
  ) {
    var cell = this.getInitialCellForEvent(me);
    this.delayedSelection = this.isDelayedSelection(cell, me);
    this.cell = null;

    if (this.isSelectEnabled() && !this.delayedSelection) {
      this.graph.selectCellForEvent(cell, me.getEvent());
    }

    if (this.isMoveEnabled()) {
      var model = this.graph.model;
      var geo = model.getGeometry(cell);

      if (
        this.graph.isCellMovable(cell) &&
        (!model.isEdge(cell) ||
          this.graph.getSelectionCount() > 1 ||
          (geo.points != null && geo.points.length > 0) ||
          model.getTerminal(cell, true) == null ||
          model.getTerminal(cell, false) == null ||
          this.graph.allowDanglingEdges ||
          (this.graph.isCloneEvent(me.getEvent()) &&
            this.graph.isCellsCloneable()))
      ) {
        this.start(cell, me.getX(), me.getY());
      } else if (this.delayedSelection) {
        this.cell = cell;
      }

      this.cellWasClicked = true;
      this.consumeMouseEvent(mxEvent.MOUSE_DOWN, me);
    }
  }
};

/**
 * Function: getGuideStates
 *
 * Creates an array of cell states which should be used as guides.
 */
mxGraphHandler.prototype.getGuideStates = function () {
  var parent = this.graph.getDefaultParent();
  var model = this.graph.getModel();

  var filter = mxUtils.bind(this, function (cell) {
    return (
      this.graph.view.getState(cell) != null &&
      model.isVertex(cell) &&
      model.getGeometry(cell) != null &&
      !model.getGeometry(cell).relative
    );
  });

  return this.graph.view.getCellStates(model.filterDescendants(filter, parent));
};

/**
 * Function: getCells
 *
 * Returns the cells to be modified by this handler. This implementation
 * returns all selection cells that are movable, or the given initial cell if
 * the given cell is not selected and movable. This handles the case of moving
 * unselectable or unselected cells.
 *
 * Parameters:
 *
 * initialCell - <mxCell> that triggered this handler.
 */
mxGraphHandler.prototype.getCells = function (initialCell) {
  if (!this.delayedSelection && this.graph.isCellMovable(initialCell)) {
    return [initialCell];
  } else {
    return this.graph.getMovableCells(this.graph.getSelectionCells());
  }
};

/**
 * Function: getPreviewBounds
 *
 * Returns the <mxRectangle> used as the preview bounds for
 * moving the given cells.
 */
mxGraphHandler.prototype.getPreviewBounds = function (cells) {
  var bounds = this.getBoundingBox(cells);

  if (bounds != null) {
    // Corrects width and height
    bounds.width = Math.max(0, bounds.width - 1);
    bounds.height = Math.max(0, bounds.height - 1);

    if (bounds.width < this.minimumSize) {
      var dx = this.minimumSize - bounds.width;
      bounds.x -= dx / 2;
      bounds.width = this.minimumSize;
    } else {
      bounds.x = Math.round(bounds.x);
      bounds.width = Math.ceil(bounds.width);
    }

    var tr = this.graph.view.translate;
    var s = this.graph.view.scale;

    if (bounds.height < this.minimumSize) {
      var dy = this.minimumSize - bounds.height;
      bounds.y -= dy / 2;
      bounds.height = this.minimumSize;
    } else {
      bounds.y = Math.round(bounds.y);
      bounds.height = Math.ceil(bounds.height);
    }
  }

  return bounds;
};

/**
 * Function: getBoundingBox
 *
 * Returns the union of the <mxCellStates> for the given array of <mxCells>.
 * For vertices, this method uses the bounding box of the corresponding shape
 * if one exists. The bounding box of the corresponding text label and all
 * controls and overlays are ignored. See also: <mxGraphView.getBounds> and
 * <mxGraph.getBoundingBox>.
 *
 * Parameters:
 *
 * cells - Array of <mxCells> whose bounding box should be returned.
 */
mxGraphHandler.prototype.getBoundingBox = function (cells) {
  var result = null;

  if (cells != null && cells.length > 0) {
    var model = this.graph.getModel();

    for (var i = 0; i < cells.length; i++) {
      if (model.isVertex(cells[i]) || model.isEdge(cells[i])) {
        var state = this.graph.view.getState(cells[i]);

        if (state != null) {
          var bbox = state;

          if (
            model.isVertex(cells[i]) &&
            state.shape != null &&
            state.shape.boundingBox != null
          ) {
            bbox = state.shape.boundingBox;
          }

          if (result == null) {
            result = mxRectangle.fromRectangle(bbox);
          } else {
            result.add(bbox);
          }
        }
      }
    }
  }

  return result;
};

/**
 * Function: createPreviewShape
 *
 * Creates the shape used to draw the preview for the given bounds.
 */
mxGraphHandler.prototype.createPreviewShape = function (bounds) {
  var shape = new mxRectangleShape(bounds, null, this.previewColor);
  shape.isDashed = true;

  if (this.htmlPreview) {
    shape.dialect = mxConstants.DIALECT_STRICTHTML;
    shape.init(this.graph.container);
  } else {
    // Makes sure to use either VML or SVG shapes in order to implement
    // event-transparency on the background area of the rectangle since
    // HTML shapes do not let mouseevents through even when transparent
    shape.dialect =
      this.graph.dialect != mxConstants.DIALECT_SVG
        ? mxConstants.DIALECT_VML
        : mxConstants.DIALECT_SVG;
    shape.init(this.graph.getView().getOverlayPane());
    shape.pointerEvents = false;

    // Workaround for artifacts on iOS
    if (mxClient.IS_IOS) {
      shape.getSvgScreenOffset = function () {
        return 0;
      };
    }
  }

  return shape;
};

/**
 * Function: start
 *
 * Starts the handling of the mouse gesture.
 */
mxGraphHandler.prototype.start = function (cell, x, y) {
  this.cell = cell;
  this.first = mxUtils.convertPoint(this.graph.container, x, y);
  this.cells = this.getCells(this.cell);
  this.bounds = this.graph.getView().getBounds(this.cells);
  this.pBounds = this.getPreviewBounds(this.cells);
  this.allCells = new mxDictionary();
  this.cloning = false;
  this.cellCount = 0;

  for (var i = 0; i < this.cells.length; i++) {
    this.cellCount += this.addStates(this.cells[i], this.allCells);
  }

  if (this.guidesEnabled) {
    this.guide = new mxGuide(this.graph, this.getGuideStates());
    var parent = this.graph.model.getParent(cell);
    var ignore = this.graph.model.getChildCount(parent) < 2;

    this.guide.isStateIgnored = mxUtils.bind(this, function (state) {
      var p = this.graph.model.getParent(state.cell);

      return (
        (!this.cloning && this.isCellMoving(state.cell)) ||
        (state.cell != (this.target || parent) &&
          !ignore &&
          (this.target == null ||
            this.graph.model.getChildCount(this.target) >= 2) &&
          p != (this.target || parent))
      );
    });
  }
};

/**
 * Function: addStates
 *
 * Adds the states for the given cell recursively to the given dictionary.
 */
mxGraphHandler.prototype.addStates = function (cell, dict) {
  var state = this.graph.view.getState(cell);
  var count = 0;

  if (state != null && dict.get(cell) == null) {
    dict.put(cell, state);
    count++;

    var childCount = this.graph.model.getChildCount(cell);

    for (var i = 0; i < childCount; i++) {
      count += this.addStates(this.graph.model.getChildAt(cell, i), dict);
    }
  }

  return count;
};

/**
 * Function: isCellMoving
 *
 * Returns true if the given cell is currently being moved.
 */
mxGraphHandler.prototype.isCellMoving = function (cell) {
  return this.allCells.get(cell) != null;
};

/**
 * Function: useGuidesForEvent
 *
 * Returns true if the guides should be used for the given <mxMouseEvent>.
 * This implementation returns <mxGuide.isEnabledForEvent>.
 */
mxGraphHandler.prototype.useGuidesForEvent = function (me) {
  return this.guide != null
    ? this.guide.isEnabledForEvent(me.getEvent())
    : true;
};

/**
 * Function: snap
 *
 * Snaps the given vector to the grid and returns the given mxPoint instance.
 */
mxGraphHandler.prototype.snap = function (vector) {
  var scale = this.scaleGrid ? this.graph.view.scale : 1;

  vector.x = this.graph.snap(vector.x / scale) * scale;
  vector.y = this.graph.snap(vector.y / scale) * scale;

  return vector;
};

/**
 * Function: getDelta
 *
 * Returns an <mxPoint> that represents the vector for moving the cells
 * for the given <mxMouseEvent>.
 */
mxGraphHandler.prototype.getDelta = function (me) {
  var point = mxUtils.convertPoint(this.graph.container, me.getX(), me.getY());
  var s = this.graph.view.scale;

  return new mxPoint(
    this.roundLength((point.x - this.first.x) / s) * s,
    this.roundLength((point.y - this.first.y) / s) * s
  );
};

/**
 * Function: updateHint
 *
 * Hook for subclassers do show details while the handler is active.
 */
mxGraphHandler.prototype.updateHint = function (me) {};

/**
 * Function: removeHint
 *
 * Hooks for subclassers to hide details when the handler gets inactive.
 */
mxGraphHandler.prototype.removeHint = function () {};

/**
 * Function: roundLength
 *
 * Hook for rounding the unscaled vector. This uses Math.round.
 */
mxGraphHandler.prototype.roundLength = function (length) {
  return Math.round(length * 2) / 2;
};

/**
 * Function: mouseMove
 *
 * Handles the event by highlighting possible drop targets and updating the
 * preview.
 */
mxGraphHandler.prototype.mouseMove = function (sender, me) {
  var graph = this.graph;

  if (
    !me.isConsumed() &&
    graph.isMouseDown &&
    this.cell != null &&
    this.first != null &&
    this.bounds != null
  ) {
    // Stops moving if a multi touch event is received
    if (mxEvent.isMultiTouchEvent(me.getEvent())) {
      this.reset();
      return;
    }

    var delta = this.getDelta(me);
    var dx = delta.x;
    var dy = delta.y;
    var tol = graph.tolerance;

    if (
      this.shape != null ||
      this.livePreviewActive ||
      Math.abs(dx) > tol ||
      Math.abs(dy) > tol
    ) {
      // Highlight is used for highlighting drop targets
      if (this.highlight == null) {
        this.highlight = new mxCellHighlight(
          this.graph,
          mxConstants.DROP_TARGET_COLOR,
          3
        );
      }

      var clone =
        graph.isCloneEvent(me.getEvent()) &&
        graph.isCellsCloneable() &&
        this.isCloneEnabled();
      var gridEnabled = graph.isGridEnabledEvent(me.getEvent());
      var hideGuide = true;
      this.cloning = clone;

      var target = null;
      var cell = me.getCell();

      if (graph.isDropEnabled() && this.highlightEnabled) {
        // Contains a call to getCellAt to find the cell under the mouse
        target = graph.getDropTarget(this.cells, me.getEvent(), cell, clone);
      }

      var state = graph.getView().getState(target);
      var highlight = false;

      if (
        state != null &&
        (graph.model.getParent(this.cell) != target || clone)
      ) {
        if (this.target != target) {
          this.target = target;
          this.setHighlightColor(mxConstants.DROP_TARGET_COLOR);
        }

        highlight = true;
      } else {
        this.target = null;

        if (
          this.connectOnDrop &&
          cell != null &&
          this.cells.length == 1 &&
          graph.getModel().isVertex(cell) &&
          graph.isCellConnectable(cell)
        ) {
          state = graph.getView().getState(cell);

          if (state != null) {
            var error = graph.getEdgeValidationError(null, this.cell, cell);
            var color =
              error == null
                ? mxConstants.VALID_COLOR
                : mxConstants.INVALID_CONNECT_TARGET_COLOR;
            this.setHighlightColor(color);
            highlight = true;
          }
        }
      }

      if (state != null && highlight) {
        this.highlight.highlight(state);
      } else {
        this.highlight.hide();
      }

      if (this.livePreviewActive && clone) {
        this.resetLivePreview();
        this.livePreviewActive = false;
      } else if (
        this.maxLivePreview >= this.cellCount &&
        !this.livePreviewActive &&
        mxClient.IS_SVG
      ) {
        this.setHandlesVisibleForCells(this.cells, false);
        this.livePreviewActive = true;
        this.livePreviewUsed = true;
      } else if (!this.livePreviewUsed && this.shape == null) {
        this.shape = this.createPreviewShape(this.bounds);
      }

      if (this.guide != null && this.useGuidesForEvent(me)) {
        delta = this.guide.move(
          this.bounds,
          new mxPoint(dx, dy),
          gridEnabled,
          clone
        );
        hideGuide = false;
        dx = delta.x;
        dy = delta.y;
      } else if (gridEnabled) {
        var trx = graph.getView().translate;
        var scale = graph.getView().scale;

        var tx =
          this.bounds.x -
          (graph.snap(this.bounds.x / scale - trx.x) + trx.x) * scale;
        var ty =
          this.bounds.y -
          (graph.snap(this.bounds.y / scale - trx.y) + trx.y) * scale;
        var v = this.snap(new mxPoint(dx, dy));

        dx = v.x - tx;
        dy = v.y - ty;
      }

      if (this.guide != null && hideGuide) {
        this.guide.hide();
      }

      // Constrained movement if shift key is pressed
      if (graph.isConstrainedEvent(me.getEvent())) {
        if (Math.abs(dx) > Math.abs(dy)) {
          dy = 0;
        } else {
          dx = 0;
        }
      }

      this.currentDx = dx;
      this.currentDy = dy;
      this.updatePreview();
    }

    this.updateHint(me);
    this.consumeMouseEvent(mxEvent.MOUSE_MOVE, me);

    // Cancels the bubbling of events to the container so
    // that the droptarget is not reset due to an mouseMove
    // fired on the container with no associated state.
    mxEvent.consume(me.getEvent());
  } else if (
    (this.isMoveEnabled() || this.isCloneEnabled()) &&
    this.updateCursor &&
    !me.isConsumed() &&
    (me.getState() != null || me.sourceState != null) &&
    !graph.isMouseDown
  ) {
    var cursor = graph.getCursorForMouseEvent(me);

    if (
      cursor == null &&
      graph.isEnabled() &&
      graph.isCellMovable(me.getCell())
    ) {
      if (graph.getModel().isEdge(me.getCell())) {
        cursor = mxConstants.CURSOR_MOVABLE_EDGE;
      } else {
        cursor = mxConstants.CURSOR_MOVABLE_VERTEX;
      }
    }

    // Sets the cursor on the original source state under the mouse
    // instead of the event source state which can be the parent
    if (cursor != null && me.sourceState != null) {
      me.sourceState.setCursor(cursor);
    }
  }
};

/**
 * Function: updatePreview
 *
 * Updates the bounds of the preview shape.
 */
mxGraphHandler.prototype.updatePreview = function (remote) {
  if (this.livePreviewUsed && !remote) {
    if (this.cells != null) {
      this.updateLivePreview(
        this.currentDx - this.graph.panDx,
        this.currentDy - this.graph.panDy
      );
    }
  } else {
    this.updatePreviewShape();
  }
};

/**
 * Function: updatePreviewShape
 *
 * Updates the bounds of the preview shape.
 */
mxGraphHandler.prototype.updatePreviewShape = function () {
  if (this.shape != null) {
    this.shape.bounds = new mxRectangle(
      Math.round(this.pBounds.x + this.currentDx - this.graph.panDx),
      Math.round(this.pBounds.y + this.currentDy - this.graph.panDy),
      this.pBounds.width,
      this.pBounds.height
    );
    this.shape.redraw();
  }
};

/**
 * Function: updateLivePreview
 *
 * Updates the bounds of the preview shape.
 */
mxGraphHandler.prototype.updateLivePreview = function (dx, dy) {
  var states = [];

  if (this.allCells != null) {
    this.allCells.visit(
      mxUtils.bind(this, function (key, state) {
        // Saves current state
        var tempState = state.clone();
        states.push([state, tempState]);

        // Makes transparent for events to detect drop targets
        if (state.shape != null) {
          if (state.shape.originalPointerEvents == null) {
            state.shape.originalPointerEvents = state.shape.pointerEvents;
          }

          state.shape.pointerEvents = false;

          if (state.text != null && state.text.node != null) {
            var node = state.text.node;

            if (
              node.firstChild != null &&
              node.firstChild.firstChild != null &&
              node.firstChild.firstChild.nodeName == "foreignObject"
            ) {
              node.firstChild.firstChild.setAttribute("pointer-events", "none");
            } else if (node.ownerSVGElement != null) {
              node.setAttribute("pointer-events", "none");
            } else {
              node.style.pointerEvents = "none";
            }
          }
        }

        // Temporarily changes position
        if (this.graph.model.isVertex(state.cell)) {
          state.x += dx;
          state.y += dy;

          // Draws the live preview
          if (!this.cloning) {
            state.view.graph.cellRenderer.redraw(state, true);

            // Forces redraw of connected edges after all states
            // have been updated but avoids update of state
            state.view.invalidate(state.cell);
            state.invalid = false;
          }

          // Hides folding icon
          if (state.control != null && state.control.node != null) {
            state.control.node.style.visibility = "hidden";
          }
        }
      })
    );
  }

  // Redraws connected edges
  var s = this.graph.view.scale;

  for (var i = 0; i < states.length; i++) {
    var state = states[i][0];

    if (this.graph.model.isEdge(state.cell)) {
      var geometry = this.graph.getCellGeometry(state.cell);
      var points = [];

      if (geometry != null && geometry.points != null) {
        for (var j = 0; j < geometry.points.length; j++) {
          if (geometry.points[j] != null) {
            points.push(
              new mxPoint(
                geometry.points[j].x + dx / s,
                geometry.points[j].y + dy / s
              )
            );
          }
        }
      }

      var source = state.visibleSourceState;
      var target = state.visibleTargetState;
      var pts = states[i][1].absolutePoints;

      if (source == null || !this.isCellMoving(source.cell)) {
        var pt0 = pts[0];
        state.setAbsoluteTerminalPoint(
          new mxPoint(pt0.x + dx, pt0.y + dy),
          true
        );
        source = null;
      } else {
        state.view.updateFixedTerminalPoint(
          state,
          source,
          true,
          this.graph.getConnectionConstraint(state, source, true)
        );
      }

      if (target == null || !this.isCellMoving(target.cell)) {
        var ptn = pts[pts.length - 1];
        state.setAbsoluteTerminalPoint(
          new mxPoint(ptn.x + dx, ptn.y + dy),
          false
        );
        target = null;
      } else {
        state.view.updateFixedTerminalPoint(
          state,
          target,
          false,
          this.graph.getConnectionConstraint(state, target, false)
        );
      }

      state.view.updatePoints(state, points, source, target);
      state.view.updateFloatingTerminalPoints(state, source, target);
      state.invalid = false;

      // Draws the live preview but avoids update of state
      if (!this.cloning) {
        state.view.graph.cellRenderer.redraw(state, true);
      }
    }
  }

  this.graph.view.validate();
  this.redrawHandles(states);
  this.resetPreviewStates(states);
};

/**
 * Function: redrawHandles
 *
 * Redraws the preview shape for the given states array.
 */
mxGraphHandler.prototype.redrawHandles = function (states) {
  for (var i = 0; i < states.length; i++) {
    var handler = this.graph.selectionCellsHandler.getHandler(
      states[i][0].cell
    );

    if (handler != null) {
      handler.redraw(true);
    }
  }
};

/**
 * Function: resetPreviewStates
 *
 * Resets the given preview states array.
 */
mxGraphHandler.prototype.resetPreviewStates = function (states) {
  for (var i = 0; i < states.length; i++) {
    states[i][0].setState(states[i][1]);
  }
};

/**
 * Function: resetLivePreview
 *
 * Resets the livew preview.
 */
mxGraphHandler.prototype.resetLivePreview = function () {
  if (this.allCells != null) {
    this.allCells.visit(
      mxUtils.bind(this, function (key, state) {
        // Restores event handling
        if (state.shape != null && state.shape.originalPointerEvents != null) {
          state.shape.pointerEvents = state.shape.originalPointerEvents;
          state.shape.originalPointerEvents = null;

          // Forces a repaint event if not moved
          state.shape.bounds = null;

          if (state.text != null && state.text.node != null) {
            var node = state.text.node;

            if (
              node.firstChild != null &&
              node.firstChild.firstChild != null &&
              node.firstChild.firstChild.nodeName == "foreignObject"
            ) {
              node.firstChild.firstChild.setAttribute("pointer-events", "all");
            } else if (node.ownerSVGElement != null) {
              node.removeAttribute("pointer-events");
            } else {
              node.style.pointerEvents = "";
            }
          }
        }

        // Shows folding icon
        if (state.control != null && state.control.node != null) {
          state.control.node.style.visibility = "";
        }

        // Forces repaint of state and connected edges
        state.view.invalidate(state.cell);
      })
    );

    // Repaints all invalid states
    this.graph.view.validate();
  }
};

/**
 * Function: reset
 *
 * Resets the state of this handler.
 */
mxGraphHandler.prototype.setHandlesVisibleForCells = function (cells, visible) {
  for (var i = 0; i < cells.length; i++) {
    var cell = cells[i];

    var handler = this.graph.selectionCellsHandler.getHandler(cell);

    if (handler != null) {
      handler.setHandlesVisible(visible);

      if (visible) {
        handler.redraw();
      }
    }
  }
};

/**
 * Function: setHighlightColor
 *
 * Sets the color of the rectangle used to highlight drop targets.
 *
 * Parameters:
 *
 * color - String that represents the new highlight color.
 */
mxGraphHandler.prototype.setHighlightColor = function (color) {
  if (this.highlight != null) {
    this.highlight.setHighlightColor(color);
  }
};

/**
 * Function: mouseUp
 *
 * Handles the event by applying the changes to the selection cells.
 */
mxGraphHandler.prototype.mouseUp = function (sender, me) {
  if (!me.isConsumed()) {
    if (this.livePreviewUsed) {
      this.resetLivePreview();
    }

    if (
      this.cell != null &&
      this.first != null &&
      (this.shape != null || this.livePreviewUsed) &&
      this.currentDx != null &&
      this.currentDy != null
    ) {
      var graph = this.graph;
      var cell = me.getCell();

      if (
        this.connectOnDrop &&
        this.target == null &&
        cell != null &&
        graph.getModel().isVertex(cell) &&
        graph.isCellConnectable(cell) &&
        graph.isEdgeValid(null, this.cell, cell)
      ) {
        graph.connectionHandler.connect(this.cell, cell, me.getEvent());
      } else {
        var clone =
          graph.isCloneEvent(me.getEvent()) &&
          graph.isCellsCloneable() &&
          this.isCloneEnabled();
        var scale = graph.getView().scale;
        var dx = this.roundLength(this.currentDx / scale);
        var dy = this.roundLength(this.currentDy / scale);
        var target = this.target;

        if (
          graph.isSplitEnabled() &&
          graph.isSplitTarget(target, this.cells, me.getEvent())
        ) {
          graph.splitEdge(target, this.cells, null, dx, dy);
        } else {
          this.moveCells(this.cells, dx, dy, clone, this.target, me.getEvent());
        }
      }
    } else if (
      this.isSelectEnabled() &&
      this.delayedSelection &&
      this.cell != null
    ) {
      this.selectDelayed(me);
    }
  }

  // Consumes the event if a cell was initially clicked
  if (this.cellWasClicked) {
    this.consumeMouseEvent(mxEvent.MOUSE_UP, me);
  }

  this.reset();
};

/**
 * Function: selectDelayed
 *
 * Implements the delayed selection for the given mouse event.
 */
mxGraphHandler.prototype.selectDelayed = function (me) {
  if (
    !this.graph.isCellSelected(this.cell) ||
    !this.graph.popupMenuHandler.isPopupTrigger(me)
  ) {
    this.graph.selectCellForEvent(this.cell, me.getEvent());
  }
};

/**
 * Function: reset
 *
 * Resets the state of this handler.
 */
mxGraphHandler.prototype.reset = function () {
  if (this.livePreviewUsed) {
    this.resetLivePreview();
    this.setHandlesVisibleForCells(this.cells, true);
  }

  this.destroyShapes();
  this.removeHint();

  this.delayedSelection = false;
  this.livePreviewActive = null;
  this.livePreviewUsed = null;
  this.cellWasClicked = false;
  this.currentDx = null;
  this.currentDy = null;
  this.cellCount = null;
  this.cloning = false;
  this.allCells = null;
  this.guides = null;
  this.target = null;
  this.first = null;
  this.cells = null;
  this.cell = null;
};

/**
 * Function: shouldRemoveCellsFromParent
 *
 * Returns true if the given cells should be removed from the parent for the specified
 * mousereleased event.
 */
mxGraphHandler.prototype.shouldRemoveCellsFromParent = function (
  parent,
  cells,
  evt
) {
  if (this.graph.getModel().isVertex(parent)) {
    var pState = this.graph.getView().getState(parent);

    if (pState != null) {
      var pt = mxUtils.convertPoint(
        this.graph.container,
        mxEvent.getClientX(evt),
        mxEvent.getClientY(evt)
      );
      var alpha = mxUtils.toRadians(
        mxUtils.getValue(pState.style, mxConstants.STYLE_ROTATION) || 0
      );

      if (alpha != 0) {
        var cos = Math.cos(-alpha);
        var sin = Math.sin(-alpha);
        var cx = new mxPoint(pState.getCenterX(), pState.getCenterY());
        pt = mxUtils.getRotatedPoint(pt, cos, sin, cx);
      }

      return !mxUtils.contains(pState, pt.x, pt.y);
    }
  }

  return false;
};

/**
 * Function: moveCells
 *
 * Moves the given cells by the specified amount.
 */
mxGraphHandler.prototype.moveCells = function (
  cells,
  dx,
  dy,
  clone,
  target,
  evt
) {
  if (clone) {
    cells = this.graph.getCloneableCells(cells);
  }

  // Removes cells from parent
  var parent = this.graph.getModel().getParent(this.cell);

  if (
    target == null &&
    this.isRemoveCellsFromParent() &&
    this.shouldRemoveCellsFromParent(parent, cells, evt)
  ) {
    target = this.graph.getDefaultParent();
  }

  // Cloning into locked cells is not allowed
  clone =
    clone && !this.graph.isCellLocked(target || this.graph.getDefaultParent());

  this.graph.getModel().beginUpdate();
  try {
    var parents = [];

    // Removes parent if all child cells are removed
    if (!clone && target != null && this.removeEmptyParents) {
      // Collects all non-selected parents
      var dict = new mxDictionary();

      for (var i = 0; i < cells.length; i++) {
        dict.put(cells[i], true);
      }

      // LATER: Recurse up the cell hierarchy
      for (var i = 0; i < cells.length; i++) {
        var par = this.graph.model.getParent(cells[i]);

        if (par != null && !dict.get(par)) {
          dict.put(par, true);
          parents.push(par);
        }
      }
    }

    // Passes all selected cells in order to correctly clone or move into
    // the target cell. The method checks for each cell if its movable.
    cells = this.graph.moveCells(
      cells,
      dx - this.graph.panDx / this.graph.view.scale,
      dy - this.graph.panDy / this.graph.view.scale,
      clone,
      target,
      evt
    );

    // Removes parent if all child cells are removed
    var temp = [];

    for (var i = 0; i < parents.length; i++) {
      if (this.shouldRemoveParent(parents[i])) {
        temp.push(parents[i]);
      }
    }

    this.graph.removeCells(temp, false);
  } finally {
    this.graph.getModel().endUpdate();
  }

  // Selects the new cells if cells have been cloned
  if (clone) {
    this.graph.setSelectionCells(cells);
  }

  if (this.isSelectEnabled() && this.scrollOnMove) {
    this.graph.scrollCellToVisible(cells[0]);
  }
};

/**
 * Function: moveCells
 *
 * Moves the given cells by the specified amount.
 */
mxGraphHandler.prototype.shouldRemoveParent = function (parent) {
  var state = this.graph.view.getState(parent);

  if (
    state != null &&
    (this.graph.model.isEdge(state.cell) ||
      this.graph.model.isVertex(state.cell)) &&
    this.graph.isCellDeletable(state.cell) &&
    this.graph.model.getChildCount(state.cell) == 0
  ) {
    var stroke = mxUtils.getValue(
      state.style,
      mxConstants.STYLE_STROKECOLOR,
      mxConstants.NONE
    );
    var fill = mxUtils.getValue(
      state.style,
      mxConstants.STYLE_FILLCOLOR,
      mxConstants.NONE
    );

    return stroke == mxConstants.NONE && fill == mxConstants.NONE;
  }

  return false;
};

/**
 * Function: destroyShapes
 *
 * Destroy the preview and highlight shapes.
 */
mxGraphHandler.prototype.destroyShapes = function () {
  // Destroys the preview dashed rectangle
  if (this.shape != null) {
    this.shape.destroy();
    this.shape = null;
  }

  if (this.guide != null) {
    this.guide.destroy();
    this.guide = null;
  }

  // Destroys the drop target highlight
  if (this.highlight != null) {
    this.highlight.destroy();
    this.highlight = null;
  }
};

/**
 * Function: destroy
 *
 * Destroys the handler and all its resources and DOM nodes.
 */
mxGraphHandler.prototype.destroy = function () {
  this.graph.removeMouseListener(this);
  this.graph.removeListener(this.panHandler);

  if (this.escapeHandler != null) {
    this.graph.removeListener(this.escapeHandler);
    this.escapeHandler = null;
  }

  if (this.refreshHandler != null) {
    this.graph.getModel().removeListener(this.refreshHandler);
    this.refreshHandler = null;
  }

  this.destroyShapes();
  this.removeHint();
};
